Frugal drivers push gallon of gas as far as it can go

They go slow, coast a lot, even draft on semis

SAUK RAPIDS, Minn. -- The passion that burns in Laurie With isn't visible until she gets behind the wheel of her Honda Civic hybrid -- and drives real slow.

She accelerates gently when the light turns green, and coasts down hills to save gasoline. On highways, she stays in the right lane and watches the big SUVs zoom past.

"When I see someone roar past me, I think, 'They just used enough gas to last me a week,' " she said.

She is part of a small and extremely dedicated group of drivers around the country who call themselves "hypermilers." They almost exclusively drive hybrid vehicles, and their goal is simple: squeeze every mile they can out of each drop of gasoline.

Some of their tips are a matter of common sense and could help any driver: avoiding jack-rabbit starts, using alternate routes to avoid stop-and-go traffic, anticipating lights and driving a bit more slowly.

But those are just a start. Hypermilers slightly overinflate their tires to cut rolling resistance, seize every chance to coast with their gasoline engines off, and sometimes "draft" like race cars behind larger vehicles.

Some of these techniques can be dangerous, and some cannot even be done in certain conventional automobiles.

Wayne Gerdes, who runs a Web site dedicated to high mileage (cleanmpg.com) and claims to have coined the term hypermiling, lists techniques:

Drafting off the rear right corner of a tractor-trailer to reduce wind resistance while still allowing the rig's driver to see you. Gerdes recommends following the truck at a gap of about one second; drafting any closer yields eye-popping gas mileage but is too dangerous, he says.

Using "pulse and glide," where the driver accelerates above the speed limit, shuts the gasoline engine down and glides to a speed below the limit. It is fairly easy to do with a hybrid, but in a gas-only vehicle, it can be dangerous because power brakes may not work and some automatic transmissions won't re-engage at highway speeds. In a gas-only vehicle, without a lot of practice, "you can wind up killing somebody," Gerdes says. (It's also illegal in a lot of places.)

Kurt Antonius, a spokesman for Honda Motor Co., said the company shares hypermilers' enthusiasm for high mileage but cannot endorse some of their techniques. "It may be great on the racetrack to do drafting, but not on the highway," he said.

Similarly, Minnesota State Patrol Lt. Mark Peterson applauded the hypermilers' goals but said that drafting less than three seconds behind tractor-trailers or shutting down a traditional engine while driving sound too dangerous.

None of that dampens hypermilers' enthusiasm. On Web sites such as Gerdes' and on greenhybrid.com, they share tales of achievement.

When a hypermiler in Japan reported averaging 112.2 mpg in her Toyota Prius II, another hypermiler responded with a barrage of technical questions about "intense pulses" and a "low state of charge on the battery."

On a sunny spring day in Sauk Rapids, With was happy to demonstrate her high-mileage techniques. Hypermiling, it turns out, looks an awful lot like Sunday driving.

With let her car roll slowly down the slope of a parking lot before starting it. She eased away from a stop sign and coasted for several blocks down a slight grade through a leafy neighborhood.

"You see a little more," she said as a playground slid past. The dashboard readout showed 59 mpg on a car the EPA estimates should get 47 in city-highway driving.

With a rural highway nearly to herself, she let the car glide well below the 50 mph speed limit. "No one's behind me, so, eh," she said with a shrug.